65 research outputs found
Pest categorisation of Anisogramma anomala
Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a pest categorisation of Anisogramma anomala, a wellâdefined and distinguishable fungal species of the family Valsaceae. The pathogen is regulated in Annex IIAI of Council Directive 2000/29/EC as a harmful organism whose introduction into the EU is banned on plants of Corylus L., intended for planting, other than seeds, originating in Canada and the USA. The fungus is native to eastern North America and causes eastern filbert blight on cultivated hazel, Corylus avellana, as well as on wild hazel (Corylus spp.). In the 1960s, the disease spread on infected plant material to Oregon, where it then threatened US hazelnut production in the Willamette Valley. The pest could enter the EU via plants for planting. Hosts and favourable climatic conditions are common in the EU, thus facilitating establishment. The pest would be able to spread following establishment through infected plants for planting and ascospore dispersal. A. anomala leads to canopy and yield loss and can cause death of Corylus trees. Should the pathogen be introduced into the EU, impacts can be expected not just on hazel as a crop and as an ornamental but also in coppices and woodlands, where Corylus species provide an important habitat. In Oregon, scouting for cankers, therapeutic pruning and copious fungicide applications are reported to be necessary (but costly measures) to continue hazelnut production in the presence of the disease. Breeding for resistance led to the selection of resistant cultivars. The main knowledge gaps concern (i) the role of deadwood and cut branches as potential entry pathways and means of spread and (ii) the susceptibility of C. avellana cultivars and of Corylus spp. in the wild in the EU. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. For regulated nonâquarantine pests, the criterion on the pest presence in the EU is not met
Pest categorisation of Bretziella fagacearum
Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a pest categorisation of Bretziella fagacearum, a wellâdefined and distinguishable fungal species of the family Ceratocystidaceae. The species was moved from the genus Ceratocystis to a new genus Bretziella following phylogenetic analysis of the species and its close relatives. The former species name Ceratocystis fagacearum is used in the Council Directive 2000/29/EC. The pathogen is regulated in Annex IAI as a harmful organism whose introduction into the EU is banned. B. fagacearum is only reported from the USA, where it causes a wilt disease on Quercus spp. Other hosts are reported based on inoculation trials, although Chinese chestnut (Castanea mollissima) is reported to be naturally infected. No North American oak species has been found to be immune to the disease. The European oak species Quercus robur, Quercus petraea and Quercus pubescens were found to be susceptible in inoculation experiments. The pest could enter the EU via wood (with and without bark, including wood packaging material), plants for planting and cut branches. Hosts and favourable climatic conditions are common in the EU, thus facilitating establishment. The pest would be able to spread following establishment by means of root grafts, insect vectors and movement of wood, plants for planting and other means. The pest introduction would have impacts in woodland and plantations, as oak wilt disease is often lethal in a short period of time. Wood treatment (debarking, kiln drying, fumigation), prompt removal of affected trees and creating rootâfree zones between affected and healthy stands are available control measures. The main knowledge gaps concern (i) the survival of the fungus in wood during transport and the association with propagation material, (ii) the presence of suitable vectors in Europe and (iii) the relative susceptibility of the oak species native to Europe under natural conditions. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. For regulated nonâquarantine pests, the criterion on the pest presence in the EU is not met
Pest categorisation of Stegophora ulmea
Following a request from the European Commission, the EFSA Panel on Plant Health (PLH) performed a pest categorisation of Stegophora ulmea, a wellâdefined and distinguishable fungal species of the family Sydowiellaceae. S. ulmea causes a tree disease known as black spot of elm (Ulmus spp.). The pathogen is reported from North America (native range) and Asia (FarâEast Russia and China), but not from the EU. S. ulmea is regulated in Council Directive 2000/29/EC (Annex IIAI) as a harmful organism whose introduction into the EU is banned on plants of Ulmus L. and Zelkova L., intended for planting, other than seeds. The pathogen has been occasionally intercepted on imported bonsai plants (and then destroyed) in the Netherlands and the UK. It could enter the EU and spread within it via plants for planting (including bonsai) and cut branches. Hosts and favourable climatic conditions are common in the EU. The European native elm species Ulmus glabra and Ulmus laevis were found to be more susceptible to the disease than North American elm species, but information is lacking on Ulmus minor. The disease is rarely fatal, but S. ulmea can cause considerable damage, particularly in wet summers. Reduction of inoculum by the removal of leaf debris and avoiding overhead watering in nurseries can reduce the risk of spread of the pathogen. The main knowledge gaps concern (i) the distribution of the pest in Asian countries, (ii) the relative role of the means of entry/spread and (iii) the potential consequences in mature tree plantations and native woodland. The criteria assessed by the Panel for consideration as potential quarantine pest are met. For regulated nonâquarantine pests, the criterion on the pest presence in the EU is not met
Pest categorisation of Davidsoniella virescens
Following a request from the European Commission, the EFSA Panel on Plant Health (PLH) performed a pest categorisation of Davidsoniella virescens, a wellâdefined and distinguishable fungal species of the family Ceratocystidaceae. The species was moved from the genus Ceratocystis to the genus Davidsoniella following a revision of the family. The former species name Ceratocystis virescens is used in the Council Directive 2000/29/EC. The pathogen is regulated in Annex IIAI as a harmful organism whose introduction into the EU is banned on plants (other than fruit and seeds) and wood (including wood which has not kept its natural round surface) of Acer saccharum, originating in the USA and Canada. The fungus is native to eastern North America and causes symptoms mainly on A. saccharum, but also on Liriodendron tulipifera. The fungus is also reported as a saprotroph on various hardwood species. The pest could enter the EU via wood, plants for planting and cut branches. Hosts and favourable climatic conditions are widespread in the EU. The pest would be able to spread following establishment through sapâfeeding insects, root grafts and movement of infected wood and plants for planting. The pest introduction could have impacts on Acer spp. and L. tulipifera trees in the EU, by causing wilting, yellowing and the development of small leaves, as well as dieback of branches and, eventually, the death of trees. Avoiding damaging trees (as wounding facilitates infection of the fungus) and maintaining healthy trees (as tree stress facilitates the disease) are available measures to reduce impacts. The main knowledge gaps concern (i) the biology and epidemiology of the pathogen (including the saprotrophic form), (ii) the role of insect vectors for entry and spread, and (iii) the susceptibility of Acer spp. either native to or more recently established in Europe. The criteria assessed by the Panel for consideration as potential quarantine pest are met. For regulated nonâquarantine pests, the criterion on the pest presence in the EU is not met
Genetic frontiers for conservation:An assessment of synthetic biology and biodiversity conservation
In recent years synthetic biology has emerged as a suite of techniques and technologies that enable humans to read, interpret, modify, design and manufacture DNA in order to rapidly influence the forms and functions of cells and organisms, with the potential to reach whole species and ecosystems. As synthetic biology continues to evolve, new tools emerge, novel applications are proposed, and basic research is applied. This assessment is one part of IUCNâs effort to provide recommendations and guidance regarding the potential positive and negative impacts of synthetic biology on biodiversity conservation; it comprises a full assessment and a short synthesis report
Physics and Chemistry of Planet-Forming Disks in Extreme Radiation Environments
Our knowledge about the formation history of planetary systems is obtained by comparing the demographics of proto-planetary disks with the exoplanetary system population. Most of the disks that we have been able to characterize to date are located in nearby low-mass star forming regions. However, it is well known that most stars form in denser environments and therefore, it is questionable that the well studied population of planet forming disks is representative of those in which most exoplanets were assembled. Due to their large distances and high densities, so far it has been impossible to study the physical and chemical properties of proto-planetary disks in massive star-forming regions. We will exploit the unique resolution and sensitivity of JWST/MIRI to explore for the first time the impact of disk evaporation on the disk structure, warm disk chemistry, and dust mineralogy, all of which are important for planet formation models and exoplanet atmosphere composition. The derived physical and chemical properties will be compared to similar data of low-mass star forming regions of JWST GTO programmes
Pest categorisation of Entoleuca mammata
Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a
pest categorisation of Entoleuca mammata, a well-defined and distinguishable fungus of the family
Xylariaceae native to North America. The species was moved from the genus Hypoxylon to the genus
Entoleuca following a revision of the genus. The former species name H. mammatum is used in the
Council Directive 2000/29/EC. E. mammata is the causal agent of Hypoxylon canker of quaking aspen
(Populus tremuloides) and other poplars (Populus spp.). The pathogen has been reported in 16 EU
Member States (MS), without apparent limiting ecoclimatic factors, but mostly (with the exception of
Sweden) with a restricted distribution. E. mammata is a protected zone (PZ) quarantine pest (Annex
IIB) for Ireland and the UK (Northern Ireland). The main hosts present in the EU (P. tremula, P. nigra
and hybrid poplars) are widespread throughout most of the risk assessment area, including the PZ.
The main means of spread are wind-blown ascospores, plants for planting and wood with bark.
E. mammata is not currently reported to be of significant economic importance in the EU MS where
the pathogen is reported, but has been shown to cause significant damage in the USA. Risk reduction
options include appropriate site selection for poplar plantations, avoiding wounds, and debarking
wood. The main uncertainties concern the distribution of the pathogen in the EU, the susceptibility of
cultivated hybrid poplars to the pathogen and thus the potential damage to poplar plantations in the
RA area. The criteria assessed by the Panel for consideration as potential PZ quarantine pest are met.
The criterion of plants for planting being the main pathway for spread for regulated non-quarantine
pests is not met: plants for planting are only one of the means of spread of the pathogen
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